1. Field of the Invention
The present invention relates to a shock absorber, and more particularly, to a shock absorber which is capable of achieving a pressure-sensitive characteristic by using a pilot valve and controlling a variable frequency characteristic, which is input from a road surface, through a lateral passage formed by an open of a guide member.
2. Description of the Related Art
Generally, a shock absorber is designed to support a weight of a vehicle body and suppress and dampen a vibration transferred from a road surface to the vehicle body, contributing to improving a ride comfort and protecting loaded goods and various parts of a vehicle.
Such a shock absorber includes a cylinder filled with a working fluid (oil), a reciprocating piston rod connected to a vehicle body, and a piston valve connected to a lower end of the piston rod to slide within the cylinder and control a flow of the working fluid.
In the case of a high functional damper (HFD), a conventional shock absorber is effective in a high-speed degressive characteristic and an ultra-low-speed tuning, but cannot variably control a damping force generated in a high-frequency mode and a low-frequency mode. Hence, the conventional shock absorber has a limitation in improving a ride comfort.